In order to enable caching, you must enable composition caching at the plug-in level by setting the value of an EnableGPUAccelerationparam element to true as part of the object tag that declares the Silverlight plug-in.

Using cached composition, you can cache visual elements as bitmaps after the first time they render. Once an object or tree of objects has been cached as a bitmap, it no longer goes through the render phase as the application refreshes, rather, just the cached bitmap is rendered. Such cached bitmap swapping can take advantage of hardware acceleration from the user’s GPU, which can yield significant performance improvements for some scenarios. To use hardware acceleration in Silverlight effectively, you should understand how Silverlight uses hardware acceleration and cached composition in its architecture and rendering pipeline, and which Silverlight objects can benefit under hardware acceleration/cached composition. For more information, see Silverlight Hardware Acceleration.

Note:

Out-of-browser applications do not have editable hosting HTML. To enable GPU acceleration for an out-of-browser application, set the attribute EnableGPUAcceleration to true on the OutOfBrowserSettings element that you declare in your Deployment XAML file.

Before you can use the CacheMode property and a BitmapCache value, you must enable the GPU acceleration feature at the plug-in level (in the HTML) by setting the value of an EnableGPUAcceleration parameter to "true".